Heretofore, compositions such as aluminum chlorhydrate, aluminum chloride and aluminum sulphate have been used in coagulating water, such as river water, or industrial discharge.
It is known that cationic polymers or aluminum compounds have been used for coagulation, and to some extent these compounds have been employed together. Further, the use of clay in treating water alone or in combination with certain aluminum compounds is known.
Several U.S. patents disclose the use of cationic polymeric coagulants with aluminum compounds, e.g. such as U.S. Pat. No. 4,559,143 to Asada et al. However, none of these patents employ aluminum chlorhydrate in their compounds.